Helicases are ATP-dependent motor proteins that translocate along single-stranded or double-stranded nucleic acids to alter base-pairing structures or molecular interactions. Helicases can be divided to monomeric and hexameric types, each with distinct ternary structures, nucleic acid-binding modes, and translocation mechanisms. It is well established that monomeric helicases translocate by the inchworm mechanism. Recent structures of different superfamilies of hexameric helicases reveal that they use a hand-over hand mechanism for translocation. Structures of bacteriophage T7 replisome illustrate how helicase and polymerase cooperatively catalyze DNA unwinding. In this review, we survey structures of monomeric and hexameric helicases and compare different mechanisms for translocation.

中文翻译：

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单体和六聚解旋酶易位的不同机制。

解旋酶是依赖于ATP的运动蛋白，它们沿着单链或双链核酸易位，以改变碱基配对结构或分子相互作用。解旋酶可分为单体和六聚体类型，每种具有不同的三元结构，核酸结合模式和易位机制。众所周知，单体解旋酶是通过尺虫机制转位的。六聚解旋酶的不同超家族的最新结构表明，它们使用移交机制进行易位。T7噬菌体复制体的结构说明解旋酶和聚合酶如何协同催化DNA解链。在这篇综述中，我们调查了单体和六聚解旋酶的结构，并比较了易位的不同机制。